YAMAMOTO Takashi <yamt@netbsd.org> writes:

> Module Name:	src
> Committed By:	yamt
> Date:		Fri Nov  4 19:39:30 UTC 2005
>
> Modified Files:
> 	src/sys/nfs: nfs_bio.c
>
> Log Message:
> nfs_bioread: push delayed truncation and tweak loop accordingly.
> PR/31926 from Jed Davis.

I can confirm that this appears to have fixed those problems; tail -f
has run for an hour and a half, generating some 380MB of ktrace, with
no evidence of file-size confusion.

-- 
(let ((C call-with-current-continuation)) (apply (lambda (x y) (x y)) (map
((lambda (r) ((C C) (lambda (s) (r (lambda l (apply (s s) l))))))  (lambda
(f) (lambda (l) (if (null? l) C (lambda (k) (display (car l)) ((f (cdr l))
(C k)))))))    '((#\J #\d #\D #\v #\s) (#\e #\space #\a #\i #\newline)))))